1. Field of the Invention
The present invention relates to a method for controlling the temperature inside a cavity of a cooling appliance provided with a temperature sensor inside the cavity and with an actuator to adjust the cooling capacity of the appliance. With the term “actuator” we intend all the actuators of the cooling appliance (compressors, dampers, valves, fans, etc.) which are used by the control system of the appliance for maintaining certain conditions in the cavity as set by the user, i.e. to adjust the cooling capacity of the appliance.
2. Description of the Related Art
Traditionally the temperature inside a refrigerator cavity is controlled by comparing the user set temperature with a measured temperature coming from a dedicated sensor. The user set temperature is converted into a Cut-off and Cut-On temperature and the measured temperature is compared to these two values in order to decide the compressor state (on/off or speed thereof in case of variable speed compressor) according to a so-called hysteresis technique. A similar approach is also used to generate over temperature alarm messages: the measured probe temperature (and some related quantities such as its derivative vs. time) is compared with a set of predetermined values and, based on the comparison, a warning or alarm message is generated. The drawbacks of this kind of known solutions are related to the fact that the look-up tables and predetermined values are the result of a compromise among all the possible work conditions. The result is a poorly controlled food temperature in response to different external temperatures, different load conditions and possible non-coherent alarm indications (false alarms or non-signaled alarms).